<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        var arr = ['red','green','blue','pink'];
        var str = '';
        var sep = '!';
        for (var i=0; i<arr.length; i++) {
            str += arr[i] + sep;
        }
        console.log(str);
    </script>
</head>
<body>
    
</body>
</html>